Scaffolding brackets

ABSTRACT

There is a bracket for use in building construction. The bracket has a support leg ( 7 ) with an attachment point ( 12 ) for, fixing onto a building frame component ( 11 ). The attachment point includes a gripping member ( 37 ) mounted on a pivotal linkage ( 14 ) extending from the support leg ( 7 ). In use of the bracket to carry a working load B the leg and. gripping member can be located against opposite faces of the building frame component so that the working load generates a clamping force on the component between the gripping member ( 17 ) and support leg ( 7 ) which resists movement of the bracket.

FIELD OF THE INVENTION

This invention relates to builders' equipment. More particularly,although not exclusively it discloses an improved bracket for buildingscaffolding.

BACKGROUND TO THE INVENTION

Examples of a top-plate-hung bracket and stud bracket as currently usedfor building scaffolding are shown respectively in FIGS. 1 and 1A. Withthe bracket of FIG. 1 the upper end of the vertical leg 1 is adapted tohang over the top plate 2 of a stud wall frame 2A and the lower end 3bears against a spreader 4 which is secured across the outer faces of atleast three studs including the one shown. A plank support member 5extends horizontally out from the vertical leg and is braced by adiagonal strut 6. In use two or more such brackets are fitted along theframe of a building structure and planks are placed across them toproduce a working platform in accordance with the relevant buildingcodes including Australian Standard AS6001-1999. This bracket can betime consuming and difficult to set up as access over the top plate forboth installation and removal is necessary. There are limitations on thevertical positioning of the bracket due to the use of the top plate forsupport. There is a substantial bending moment placed on the frameresulting from loading concentrations on the top plate and bottomspreader which causes the stud to twist and deform laterally. Thebracket also puts a heavy reliance on welded joints at the upper end ofthe leg which must carry substantially the whole weight of the assembly.With the stud bracket of FIG. 1A the horizontal plank support 6A andstrut 6B are attached directly to upper and lower spreaders 6C and 6Dwhich extend across stud 6E and the adjacent studs. In this case themajority of the load is carried by the lower spreader which is onlynailed or pinned in place. Also, the oppositely directed point loadsfrom the spreaders creates a pinching action on stud 6E which deformsit.

SUMMARY OF THE INVENTION

It is therefore an object of this invention to ameliorate theaforementioned disadvantages and accordingly a bracket is disclosed foruse in building construction, said bracket having a support leg with atleast one attachment point for fixing onto a building frame component,said attachment point including a gripping member mounted on a pivotallinkage extending from said support leg whereby in use of the bracket tocarry a working load said leg and gripping member can be located againstopposite faces of the building component so that the working loadgenerates a clamping force on said component between the gripping memberand support leg which resists movement of said bracket.

Preferably but not essentially said gripping member comprises a frictionmember.

It is further preferred that the friction member includes a plate with afluted or grooved surface for enhanced grip on the building component.

It is further preferred that said linkage means comprise a U-shapedstrap.

BRIEF DESCRIPTION OF THE DRAWINGS

The currently preferred embodiments of this invention will now bedescribed with reference to the attached drawings in which:—

FIG. 2 is a schematic side elevation view of a scaffold bracketaccording to said invention,

FIG. 2A is an end elevation view of the bracket of FIG. 2 along thedirection of arrow A,

FIG. 3 is a schematic side elevation view of the bracket of FIG. 2 witha stanchion socket fitted,

FIGS. 4 and 4A show a schematic side elevation view and perspective viewof a second embodiment of the invention,

FIG. 5 shows a schematic side elevation view of a third embodiment ofthe invention,

FIGS. 6 and 6A show a schematic side elevation view and perspective viewof a fourth embodiment of the invention, and

FIGS. 7 and 7A show a schematic side elevation view and perspective viewof a fifth embodiment of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring first to FIGS. 2 and 2A there is shown a scaffold bracket ofwelded steel construction. In accordance with known design it comprisesa vertical support leg 7, horizontal platform support or plank support 8and diagonal brace 9. An end plate 10 is also provided at the outer endof the plank support which is of sufficient height to containoverlapping platform planks (not shown). The cross-sectional dimensionsof the members used to construct this bracket are in accordance with therelevant industry standards and would be known to a person skilled inthe art. The size of the bracket can be varied depending upon whether asingle or multi-plank platform is used.

In accordance with this invention the vertical leg 7 of the bracket isfixed to a building frame stud 11 at upper and lower attachment pointsindicated generally as 12, 13. The upper point comprises a U-shapedstrap 14 which is pivotally attached across its open end to the leg 7 bya bolt or pin 15. The opposite closed end 16 of the strap extends aroundthe inner face 11A of the stud as well as a friction plate 17. The strapis also pivotally attached to the friction plate by a second bolt or pin17A. A clearance space is provided between the end 16 of the strap andthe plate 17 to allow for pivoting movement.

The lower attachment point 13 comprises a pair of flanges 18 whichextend out from the leg 7 and closely straddle opposite sides 11B of thestud. In order to comply with industry standards spreaders 19, 20 arenailed in place adjacent the upper and lower attachment points todistribute or share the loading across adjacent studs (not shown) oneach side. Spreader 19 is preferably located immediately above thefriction plate. Spreader 20 is preferably located in a niche formedbetween a shoulder 21 extending down from the bottom of the leg 7 andthe stud 11. In order to allow for vertical movement of the leg when thebracket is loaded a gap 21A of at least 20 mm between the spreader 20and said leg 7 is preferred.

When the bracket is installed as shown and carries a load B from aworking platform the surface resistance between the friction plate 17and stud 11 together with the downward force on leg 7 generates aturning moment or couple 21 on the strap which clamps the stud 11 atthis point and compresses it along a vertical plane between said plate17 and leg 7. The magnitude of this clamping force on the stud isdetermined by the size of the platform load. The inventor has found thatthis novel clamping arrangement reduces twisting and lateral deformationof the stud as is encountered with prior art brackets. A scaffoldbracket according to this invention thus provides a stronger and safersupport for working platforms.

Although the plate 17 may be fluted or grooved to increase grip on thestud as described earlier the depth of these flutes or grooves ispreferably chosen to limit excessive penetration or biting into the studwhich could reduce strength. A clout 22 is also preferably driventhrough the strap and into the stud adjacent the friction plate to holdsaid plate at the position shown prior to loading.

This version of the bracket may also be fitted with a stanchion socket23 as shown in FIG. 3 which contains the planks instead of the end plate10. The socket is adapted to receive a guard-rail stanchion (not shown)for edge protection. Additional support for the guardrail againsttransverse loading can be obtained by fitting a gusset 23A between thesocket 23 and horizontal member 8.

With the second to fifth embodiments of the invention shown respectivelyin FIGS. 4 to 7A the main components that correspond in function tothose of FIGS. 2 and 2A are identified by the same numbers which howeverare primed (′), (″), (′″) and (″″) to distinguish them.

With reference to FIGS. 4 and 4A the second embodiment of the inventioncomprises a floor edge rail bracket. There is a vertical stanchion 24with guard-rails 25 which is attached to the support leg 7′ by a pair ofshort horizontal bars 26 so that it is positioned up against the floorjoist 26A and close to the edge of an elevated deck area 27. There is asingle attachment point near the lower edge of the leg with pivotedstrap 14′ and friction plate 17′ which in use of the bracket are securedclose under the top plate 28 on a wall stud 11′. With this embodimentthe angle A of the strap 14′ should be not more than about 20 degrees tothe horizontal.

The third embodiment of the bracket shown in FIG. 5 is a roof railbracket and post assembly where the stanchion 29 is shown fitted intosocket 23″. The strut 9″ in this case is located above the horizontalmember 8″. The lower attachment point also comprises a second U-shapedstrap 31 which is bolted at 32 to the vertical leg 7″ and is held inposition against the stud 11″ by a clout 33″. This strap 31 operates inthe same way as the flanges 18 of the first embodiment but has theadvantage of being readily removable at the completion of brickwork.There is a reinforcing gusset 23″ fitted between the socket 23″ andstrut 9″.

The fourth embodiment of the bracket shown in FIGS. 6 and 6A is anotherform of roof rail bracket and post assembly. Here the support leg 7′″ isadapted for fitting horizontally along the underside of a roof truss 34.There is a friction plate 17′″ at one end of the support leg 7′″ with asingle pivotal strap 14′″ which extends around the roof truss member 34and is orientated to hold the other end of the leg 7′″ hard against theinside of the top plate 35. The stanchion 36 with guard-rails 37 fitsinto a socket assembly 38 welded to the leg 7′″ and is positioned oversaid top plate (FIG. 6). Alternatively the socket and stanchion can bemounted further out on an extension arm 39 (FIG. 6A).

The fifth embodiment of FIGS. 7 and 7A is a roof rail gable bracket. Inthis case the horizontal support leg 7″″ is adapted to fit along the topof a block 40 between adjacent roof trusses 40A and 40B. There is also asecond U-shaped strap 41 and friction plate 42 located at the oppositeend of the support leg 7″″. These straps are angled in oppositedirections as shown to lock the bracket against transverse movementalong the block. The stanchion 43 with guard-rails 44 fits into a socketassembly 45 welded to the outboard end of the support leg 7″″ whichextends out onto the gable outrigger 46.

It will thus be appreciated that this invention at least in the form ofthe embodiments disclosed provides a novel and improved form of scaffoldbracket for working platforms and/or edge rail protection. Clearlyhowever the examples described are only the currently preferred forms ofthe invention and a wide variety of modifications may be made whichwould be apparent to a person skilled in the art. For example the sizeand design of the bracket as well as the shape and configuration of thestraps and friction member may be changed according to installationrequirements. Also, the contacting surface of the friction member coulduse means other than flutes or grooves such as a layer of rubber orother non-slip material to obtain a frictional grip without departingfrom the scope of the invention. The invention is further not limited toany specific material for constructing the bracket although a structuralsteel conforming to the requirements of the relevant industrialstandards is preferred for the described embodiments.

1. A bracket for use in building construction, said bracket having asupport leg with an attachment point for fixing onto a building framecomponent, said attachment point including a gripping member mounted ona pivotal linkage extending from said support leg whereby in use of thebracket to carry a working load said leg and gripping member can belocated against opposite sides of the building frame component so thatthe working load generates a clamping force on said component betweenthe gripping member and support leg which resists movement of saidbracket.
 2. The bracket as claimed in claim 1 wherein said bracket is ascaffold bracket with said support leg, when in a position of use, beingsubstantially vertical and said scaffolding bracket further including aplank support for a work platform which projects substantiallyhorizontally out from said support leg.
 3. The bracket as claimed inclaim 2 wherein said attachment point is a first attachment pointlocated adjacent an upper end of the support leg and said scaffoldbracket further including a second lower attachment point having a pairof flanges which extend out from said support leg to closely straddlesaid building frame component.
 4. The bracket as claimed in claim 5wherein a socket is located on an end plate of said plank support toreceive a guard-rail stanchion.
 5. The bracket as claimed in claim 4wherein said pivotal linkage is a U-shaped strap and said grippingmember is a friction member.
 6. The bracket as claimed in claim 1wherein said bracket is a floor edge rail bracket with said support leg,when in a position of use, being substantially vertical and said bracketfurther including a vertical stanchion attached to said support leg byhorizontal bars, said attachment point being toward a lower end of saidsupport leg and being locatable close under a building frame top plate.7. The bracket as claimed in claim 6 wherein said pivotal linkage is aU-shaped strap and said gripping member is a friction member.
 8. Thebracket as claimed in claim 1 wherein said bracket is a roof railbracket and includes, when in a position of use, a horizontal socketmounting bar for a guard-rail stanchion extending out from said supportleg and said attachment point is a first attachment point locatedadjacent an upper end of said support leg and said roof rail bracketfurther includes a second lower attachment point which operates in thesame manner as said first attachment point.
 9. The bracket as claimed inclaim 9 wherein said pivotal linkage is a U-shaped strap and saidgripping member is a friction member.
 10. The bracket as claimed inclaim 1 wherein said bracket is a roof rail bracket with said supportleg, when in a position of use, being substantially horizontal forfitting to the underside of a roof truss, said attachment point beinglocated adjacent one end of said support leg and a stanchion socketbeing fitted to the other end of said leg in a manner to locate above abuilding frame top plate.
 11. The bracket as claimed in claim 10 whereinsaid pivotal linkage is a U-shaped strap and said gripping member is afriction member.
 12. The bracket as claimed in claim 1 wherein saidbracket is a roof rail gable bracket with said support leg, when in aposition of use, being substantially horizontal for fitting to the topof a roof member and said attachment point is a first attachment pointlocated adjacent one end of said support leg and said roof rail gablebracket includes a second attachment point located adjacent the otherend of said support leg which operates in a similar manner as said firstattachment point.
 13. The bracket as claimed in claim 12 wherein saidpivotal linkage is a U-shaped strap and said gripping member is afriction member.